Just like in the movies, T. Rex king of predatory food chain

Hollywood movies got it right. Tyrannosaurus rex hunted down and killed its prey, according to new evidence that disproves long-debated theories that the dinosaur only scavenged from carcasses.

A recent discovery of a T. rex tooth lodged in the spine of a smaller plant-eating dinosaur provides “unambiguous evidence that the T. rex was an active predator,” according to a report published yesterday in Proceedings of the National Academy of Sciences. David Burnham, a lead researcher from the division of vertebrate paleontology at the University of Kansas calls the finding “the holy grail” of paleontology.

“It sends a chill down your spine, that T. rex was the monster in Jurassic Park that would hunt you down and kill you.” Burnham said in a telephone interview.

The 40-foot-long animal weighing about 7 tons has often been portrayed as the terrifying villain of dinosaur epics. Until the findings released yesterday, however, there was no scientific proof. While previous discoveries have found dinosaur bones in the T. rex stomach, they didn’t indicate whether the animals were alive when eaten.

Some scientists have argued that T. rex was too slow to capture prey and had physical characteristics of a scavenger of dead animals rather than hunter of live prey.

Healed wounds on smaller dinosaurs indicate to scientists where a predator attacked them. While paleontologists have seen marks that could have come from a T. rex attack, such as punctured bones or tooth marks, there was no direct link. The new evidence is rare for good reason – prey rarely gets away, according to the report.

In this case, one hadrosaur, a 35-foot-long plant-eating dinosaur, escaped to tell the tale 65 million years later of its attacker through a tooth lodged in its back.

Paleontologist Robert DePalma from the Palm Beach Museum of Natural History in Fort Lauderdale found parts of the hadrosaur skeleton in the Hells Creek Formation of South Dakota. When they scanned its fused vertebrae, the scientists discovered an embedded crown tooth inside the old wound. An extensive database of dinosaur teeth enabled the team to accurately identify the tooth as belonging to a T. rex.

“We have the bullet and the smoking gun,” Burnham said. He says this discovery returns T. rex to the top of the paleolithic food chain.

The finding also allows paleontologists to reconstruct the interaction between predators and prey in greater detail, he said. The finding doesn’t mean that the T. rex was only a hunter, as it almost certainly did scavenge carcasses as well, researchers said.